Conventionally, an image sensing apparatus such as an electronic camera is known which records and reproduces a still picture or an moving picture with a recording medium such as a memory card having a solid state memory device as a recording medium. Some type of such an apparatus is provided with not only an optical finder (OVF) but also an electronic finder composed of a color liquid crystal panel or the like.
This image sensing apparatus is configured such that an image of a subject is sensed by an image sensing device such as a CCD to obtain an image signal, and processing such as auto-focus (AF) control, automatic exposure (AE) control and auto-white balance (AWB) are performed using the signal. In order to display a favorable moving picture on the electronic finder, it is necessary to supply an image signal in the order of 60 frames per second. In addition, in the case in which a still picture is sensed, it is important not to miss timing for releasing a shutter. For this purpose, the above-mentioned processing such as AF control, AE control and AWB control is required to be performed at a high speed.
However, focusing cannot always be attained using an image signal of one frame and an AF control operation is performed using an image signal of a plurality of frames with the above-mentioned conventional image sensing apparatus. Thus, there is a problem in that the AF control processing takes long and, as a result, the interval between the time when a shutter button is pressed and the time when an image of a subject is actually sensed (shutter time lag) tends to be long.